Assessing Someone Intoxicated on MDPV: A Mental Health Social Workers Perspective

It’s 2 AM, and I’ve been called to A&E to assess a man brought in by the police. He’s pacing, sweating buckets, and talking non-stop—mostly about how “they” are after him. His pupils are like black holes, and he keeps darting glances towards the door as if he’s expecting someone to burst through at any moment. The police are agitated too—apparently, he was found running in and out of traffic, screaming that he was being hunted by invisible agents.

This isn’t my first time dealing with MDPV intoxication, and I doubt it’ll be my last. But every time, it’s a challenge. How do you assess mental health and capacity when someone is in the grip of a stimulant-induced paranoid psychosis?

Step One: Is This Mental Illness or Drug Intoxication?

First, I have to determine whether this is a psychiatric crisis, a substance-related episode, or both.

MDPV is a powerful stimulant, often compared to methamphetamine but with even more paranoia and aggression. The people I see on it often present as if they’re in the middle of a severe psychotic episode:

• They’re terrified. Not just anxious—absolutely convinced that someone or something is after them.

• They can’t stop moving. Pacing, twitching, or sometimes lashing out.

• They’re ranting, but it’s disjointed. A mix of grandiosity, paranoia, and confusion.

• Their perception of reality is utterly distorted. Hallucinations are common—seeing figures in the shadows, hearing voices, or feeling like bugs are crawling under their skin.

Now, if this were a first episode of schizophrenia, I’d expect a more gradual onset rather than this sudden explosion of symptoms. Bipolar mania? Maybe, but there’s usually some background history. The timeline is everything here. If they were fine yesterday and now they’re convinced MI5 is tracking them through their shoelaces, it’s likely drug-induced.

But the tricky part? Stimulant psychosis can last for days, sometimes even weeks. If I assume it’s “just the drugs,” I might miss an underlying condition. So, I have to tread carefully.

Step Two: Can They Make Decisions Right Now?

Now comes the capacity question.

Under the Mental Capacity Act 2005, someone has to be able to:

1. Understand the information relevant to the decision.

2. Retain that information.

3. Weigh it up to make an informed choice.

4. Communicate their decision.

Sounds simple enough—until you throw MDPV into the mix.

Right now, this man thinks the police are part of a conspiracy and that if he stays here, he’ll be tortured. He’s demanding to leave. He’s clearly unable to weigh up risks rationally. But does that mean he lacks capacity?

Here’s the dilemma: being intoxicated alone doesn’t mean you lack capacity. If a drunk person insists on going home rather than sobering up in hospital, we don’t necessarily override them. But MDPV scrambles the brain to the point where decision-making is impossible—this isn’t just someone being reckless.

So, I assess:

• Does he grasp the risks of leaving? No. He believes the real danger is staying here.

• Can he retain information? Not really—his thoughts are bouncing all over the place.

• Is he able to weigh up the situation? Absolutely not—his paranoia is overriding all logic.

• Can he communicate a coherent choice? He is speaking, but it’s delusional, not reasoned decision-making.

In my view, he lacks capacity at this moment—not permanently, but right now, he’s incapable of making a rational choice about his safety.

Step Three: Do I Use the Mental Health Act or the Mental Capacity Act?

This is where it gets complicated.

1. Section 136 of the Mental Health Act (MHA)

• He was brought in by the police under s136 MHA, which allows them to detain someone in a public place if they believe the person is mentally unwell and a danger to themselves or others.

• But MDPV alone isn’t a “mental disorder” under the MHA—so is this enough to justify further detention under the Act?

2. Section 2 of the MHA (for assessment and treatment)

• If I suspect an underlying mental illness, I might consider detaining him under Section 2 for further psychiatric assessment.

• But if his symptoms wear off in 24 hours, do I really want to section him?

3. The Mental Capacity Act (MCA) & Deprivation of Liberty Safeguards (DoLS)

• If this is purely drug-related, the MCA might be more appropriate—I could keep him in hospital on a temporary basis using DoLS.

• This allows short-term treatment and observation until he regains capacity.

Ultimately, I have to decide: MHA or MCA?

Since MDPV-induced psychosis can persist beyond intoxication, I’m leaning towards using the Mental Health Act, at least for a short-term assessment period. But I also know that as soon as the drugs wear off, he might make a miraculous recovery.

Step Four: Managing Risks and Next Steps

Once he’s stabilised, I need to think long-term.

• What’s his history? Is this a one-off bender, or is he a chronic MDPV user with repeated psychotic episodes?

• Does he need substance use treatment? Realistically, most drug services aren’t set up to deal with people in crisis. They’ll see him later, when he’s sober. But right now? He needs monitoring, not rehab.

• Will he be safe to leave? If his paranoia doesn’t settle, he’s at serious risk of harm—whether from running into traffic again or getting into fights with imagined enemies.

Once he starts coming down, we’ll reassess capacity again. If he regains the ability to make decisions, we can’t hold him against his will. But if he’s still delusional, the MHA might be necessary for ongoing care.

Final Thoughts: What This Case Tells Us

Assessing capacity and mental health under intoxication is never straightforward, especially with MDPV. The key takeaways?

1. Capacity isn’t black and white. Someone might appear momentarily lucid, but their overall ability to make rational decisions is impaired.

2. MDPV can cause prolonged psychosis. It’s not always just a matter of “waiting for it to wear off.”

3. Mental Health Act vs Mental Capacity Act? It depends. If I suspect underlying mental illness, I’ll lean towards the MHA. If it’s purely drug-induced, the MCA might be more appropriate.

4. Risk management is everything. Whether it’s self-harm, aggression, or impulsive behaviour, the safety of the individual (and others) is my priority.

As I finish my notes, he finally stops pacing. He sits down, staring at his hands. I ask him how he’s feeling.

“They’re still out there, but maybe… maybe I just need to sleep.”

It’s a start. We’ll see where he is in the morning.